class Solution:
    word_dic = {"A": 1, "B": 2, 'C': 3, "D": 4, "E": 5, "F": 6, "G": 7, "H": 8, "I": 9, "J": 10, "K": 11, "L": 12,
                "M": 13, "N": 14, "O": 15, "P": 16, "Q": 17, "R": 18, "S": 19, "T": 20, "U": 21, "V": 22, "W": 23,
                "X": 24, "Y": 25, "Z": 26}

    def titleToNumber(self, s: str) -> int:
        s, res = s[::-1], 0
        for index, alp in enumerate(s):
            res += Solution.word_dic[alp] * (26 ** index)
        return res


a = Solution()
print(a.titleToNumber("A"))
print(a.titleToNumber("AB"))
print(a.titleToNumber("ZY"))
